Grinding machine



Aug. 11, 1931. E. A. WALKER GRINDING MACHINE File Nov.- 1928 6 Sheets-Sheet l Aug. 11, 1931. E. A. WALKER GRINDING MACHINE Filed Novfi fi, 1928 e Sheets-Sheet 2 IQN N QN M E J Q J Ill! NNN

E. A. WALKER GRINDING MACHINE Filed No Aug. 11, 1931.

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Aug. 11,1931. E. A. WALKER GRINDING MACHINE Fil O .71928 6 Sheets-Sheet 4 Aug. 11, 1931, E. A. WALKER GRINDING MACHINE Filed O 1928 6 Sheets-Sheet 5 6 sheets-gheet 6 fidercz FflJ'ZA E. A. WALKER GRINDING MACHINE Filed Nov.

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iterate erase @F ERNEST WALKER, F .W'QBGESTER, MihfiSACHUSETTS, ASSIGNOB, BY MESNE ASSIGN- MEETS, TO JOHN BATE, GE WQBCESTER, MASSACHUSETTS GRINDING MACHINE Application filed November 15, 1928. Serial No. 319,614.

llhis invention relates to a machine particularly designed for grinding threaded work, although well adapted to the grinding of other Cylindrical work. Grinding machines of this type areoften required to accommodate work of widely varying length, which necessitates provision for extensive table travel, although the actual required travel during the grinding operation is usually rela- 1o tively short.

It is the general object of my invention to provide a grinding machine in which the work is mounted on a work table having a relatively short range of travel, and in which the grinding wheel and wheel head are mounted on a secondv slide or wheel table which is fixed in longitudinal position during a grinding operation, but which has a fairly wide range of manual adjustment by which the grinding wheel may be moved axially to a position opposite any desired part of a long piece of work.

My invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

A preferred form of the invention is shown in the drawings in which Fig. l is a plan view of my improved grinding machine;

Fig. 2 is a partial front elevation thereof, rooking in the direction of the arrow 2 in ig. l

Fig. 3 is a detail end elevation, looking in the direction of the arrow 3 in Fig. 2;

Fig. 4 is a sectional front elevation, taken along the line H in Fig. 3

Fig. 5 is a sectional end elevation, taken along the line 55 in Fig. 2;

Fig. 6 is a plan view of the work driving head, looking in the direction of the arrow 6 in Fig. 5;

Fig. 7 is a detail sectional front elevation, taken along the line 77 in Fig. 6;

Fig. 8 is a side elevation of the grinding wheel head;

Fig. 9 is a detail plan view, looking in the direction of the arrow 9 in Fig. 8;

Fig. 10 is a detail sectional rear elevation, taken along the line l0-10 in Fig. 8;

Fig. 11 is a rear view of the grinding wheel head, looking in the direction of the arrow 11 in Fig. 8; and

Fig. 12 is a detail sectional view, taken along the line 1212 in Fig. 1.

Referring to the drawings, 1 have shown my improved grinding machine as provided with a bed 20 having guideways 21 and 22 (Fig. 1) for a grinding wheel table or slide 23. The bed 20 (Fig. 5) is also provided with a base'plate 25 secured thereto and having a swivel plate 26 supported thereby, said swivel plate being mounted for angular ad- ]ustment about the axis of a stud or pivot member 27. Bolts 28 extend through slots in the base plate 25 and are effective to hold the base plate and swivel plate in angularly adjusted relation.

The swivel plate 26 is provided with guideways 29 and 30 for a work table 31 on which a Work head 32 and tail stock 33 (Fig. l) are secured in longitudinally adjusted relation.

Wheel head mechanism in a bearing 39 secured to the end of the bed 20.

lhe feed screw 38 is held from axial movement in the bearing 39 and is provided with the usual hand wheel 41. By rotation of the hand wheel, the table 23 may be adjusted along the guideways 21 and 22. It will be noted that these guideways are of substantial extent and also that the table 23 is of substantial length, so that a relatively long travel of the table 23 is available.

The grinding wheel W (Fig. 8) is mounted on a wheel spindle 44, rotatable in a bearing member 45, secured at the front end of a wheel head 46. The wheel head 46 has a base or supporting portion 47 slidable in guideways 4:8 and 49 on a secondary slide 50, which in'turn.

is slidable in guideways 51 and 52 on the -,J-.- ".4. A4! UL... m. usunent U1. we secondary slide 50 and a slow or fine adjustment of the wheel head 46 on the slide 50...

Quick adjustment For quick adjustment of the secondary slide 50, I provide a rack 54 on the table 23 and a pinion 55 (Fig. 11) mounted on a short shaft 56 having a bearing in the slide 50. A collar 57 is secured to its outer end and is provided with a plurality of radial openings 58, adapted to receive the end of a rod or handle 60 (Fig. 8). By inserting the handle 60 in successive holes, the wheel and wheel head may be quickly moved toward or from the work.

To secure the table 50 after such adjustment, I provide a clamping member 62 (Fig. 10) vertically slidable between depending Y projections 63 and 64 on the under side of the slide 50. The member 62 is shaped at its lower end to enter a T-slot 65 in a plate 66 secured 'to the table 23. A clamping rod 7 0 extends through bearings in the projections 63 and 64 and has a rear bearing in an additional projection 71. a

The rod 70 is provided with a handle 72 and has an eccentric portion 73 (Fig. 10) extending through an opening 74 in the clamping member 62. When the handle 7 2 is turned to raise the eccentric portion 73 to the position shown in Fig. 10, the clamping member 62 is drawn firmly upward against the shoulder of the T-slot 65 in the bar 66 and the slide 50 is thus firmly held from forward or rearward movement.

Fi/ne adjustment at the upper front end of an inclined shaft 81,

rotatable in hearings in the wheel head and having a worm 82 (Fig. 9) fast thereon and meshing with a worm gear 83 on an inclined intermediate shaft 84, also rotatable in bearings in the wheel head 46.

At its lower end, the shaft 84 is provided with a bevel gear 85 engaging a bevel pinion 86 on a feed screw 87. The feed screw 87 is rotatable in bearings in the base ortion 47 of the wheel head 46, but is held rom axial movement therein. 4

The rear portion of the feed screw 87 is threaded into a nut 88, held in a bracket 89 bolted to the rear end of the secondar slide 50. A graduated disc 91 is provided a jacent the hand wheel 80 and co-operates with a fixed index line to indicate the amount of the fine adjustment of the wheel occasioned by have also provided for clamping the secondary slide 50 in adjusted position and have provided a fine graduated adjustment of the grinding wheel on the slide 50 toward and from the work. i

, On the side .of the wheel head 46, I provide a dove-tailed projection 97 (Fig. 11) for a stand 98 (Fig. 1) on which a truing device slide 99 is adjustable toward and from the wheel W. The truing devices are not shown herein as their detail constru'ctionforms no part of my present invention.

The grinding wheel is provided with a pulley 92 and is driven by a belt B passing around guide pulleys 93, 94 and 95 (Fig. 8), all carried by the wheel head 46.

Work holdi/ng 'meclumz'mtv I will now describe my improved" mechanism for supporting and rotating the work.

The tail stock 33 is provided with a center 100 (Fig. 1) and with a handle 101 for withdrawing the same, the center being preferably restored to operative position by a suitable spring. The details of construction of my tail stock do not form part of my present invention.

The head center 103 (Fig. 7) is mounted in a work spindle 104, rotatable in bearings in the head 32 and having a worm wheel 105 secured thereto at its middle ortion. The worm wheel 105 is engaged by a worm 106 (Fig. 6) on a short horizontal worm shaft clamped to the head 32.

- At its front end, the shaft 107 is provided with a worm wheel 110 engaged by a worm 111 on a drive shaft 112 having a driving pulley 113 mounted thereon. The pulley 113 is rotated by a belt B (Fig. 2) from a suitable motor or other source of power (not shown).

A slotted disc or other driving device 115 may be provided on the head center 103 for engagementby a dog 116 on the work K, as

indicated in Fig. 1.

By the construction described, the work K is rotated at a greatly reduced speed from the drive shaft 112 and with an unusually smooth and even motion.

Work table feed The longitudinal feed of the work table 31 is derived from a pinion 120 (Fig. 7) mounted at the rear end of the work spindle 104 and engaging an intermediate gear 121 (Fig. 3), which in turn meshes with a gear 122, mounted on the outer end of a short lead screw 125.

The intermediate gear 121 is mounted on a aeraaes stud 126 adjustable in a'slot 127 in a gear plate 128, which is angularly adjustable about the axis of the lead screw 125 and which may be secured in adjusted position by clamping screws 129.

It may at times be desirable to reverse the motion of the lead screw relative to the rotation of the work by introducing an additional intermediate gear between the pinion 120 and the lead screw gear 122. For this purpose I have provided a second slot 130 in the plate 128.

The provision of the slots 127 and 130 in the gear plate 128 enables me to change the ratio of movement of the work table as desired and in accordance with the pitch of the thread to be ground, this being accomplished by changing the pinion 120, or the lead screw gear 122, or both.

The lead screw 125 is rotatable in a hearing 132 in the head 32 but is held from axial movement therein by a collar 133 and lock nut 134. The other end of the lead screw 125 is rotatable in a bearing 136 on the under side of the work table 31.

The lead screw 125 is threaded in a nut 140 secured in a projection 141 extending upward from the swivel table 26. The nut 140 thus remains in fixed position during the operation of the machine, while the lead screw 125 worms itself into or out of the nut 140, carrying the table 31 and head 32 with it The mechanism for controlling the movements of the work table form no part of my present invention, but I have indicated stop dogs 150 and 151 (Fig. 2) adjustably secured in a T-slot on. the front of the work table 31 and adapted to engage a lever 142 (Fig. 2) extending upward from a switch 143. When the lever 142 is engaged by either one of the dogs 150 or 151, the lever is moved to neutral position and the work table is brought to rest.

. A series of control buttons 145, 146 and 147 (Fig. 1) may be provided at the front of the machine by means of which the work table may be started in either direction or may be brought to rest at any desired point.

My improved grinding machine, while capable of general operation, is designed more particularly for grinding screw threads on taps or other threaded work, and it has been found that in such work the over-all dimensions vary widely but the actual length to be threaded in any one operation is usually comparatively short. An example of such work is indicated at K in Fig. 1, showing a shaft or spindle of considerable length but having three relatively short threaded portions formed thereon.

It will be noted that the lead screw 125 for the work table 31 is relatively short when compared with the lead screw 38 (Fig. 1) for the wheel slide 23. By the provision desired speed past the grinding wheel during the threading or grinding operation. I 7 One advantage of this construction lies in the fact that the lead screw 125 is used substantially throughout its length in ordinary grinding or threading operations,

so that the wear on the lead screw 125 is uniformly distributed. In previous machines,

where a long lead screw was used for reciprocating the work, it was found that a very largepart of the wear came on anarrowly restricted portion of the lead screw, while the larger part of the lead screw received a very little wear.

In the courseof time, wear of the parts would cause the nut to fit somewhat loosely on the short portion of the screw where most of the wear occurred, while still fitting snugly in the remaining portion. This was objectionable, as it was not possible to tighten the nut to fit the worn portion without causing it to stick on the remaining portions which had much less use and practically no wear.

Furthermore, the short travel of my work table 31 enables me to reduce the length of the guideways and to avoid excessive overhang of the parts in any position of the table.

I have thus provided a machine which is particularly adapted for guiding or threading operations on work of widely varying length and l have provided quickacting and easily operable mechanism for bringing the grinding wheel to any desired zone of grinding operations and for moving the grinding wheel toward and from work, either rapidly or gradually.

Having thus described my invention and the advantages thereof. 1 do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what 1 claim is 2- 1. In a grinding machine, a grinding wheel, means to support the grinding wheel and work to rotate on substantially parallel axes, means to adjust the wheel toward and from the work, means to move the wheel axially over an extended range of adjustment relative to the work, and additional means to move the work and work supporting means axially of the wheel over a limited range of operative movement. relative to the wheel, and means to limit said range of operative movement.

2. A grinding machine having, in combination, a grinding wheel and wheel head, a

'7 head over an extended range of axial adjustrelative to the work past said work table, and

ment relative to the work paralleling said table, and means to move said work table over a limited range of axial travel, relative to the wheel, and means to limit said range of operative movement.

3. A grinding machine having, in combination, a grinding wheel and wheel head, a table on which the work is supported with its axis substantially parallel to the axis of the wheel, means to adjust the wheel toward and from the work, means to move said wheel head over an extended range of axial adjustment means to move said work table over a limited range of axial travel, relative to the wheel, and means to limit said range of operative movement, saidwheel head being fixed and said work supporting table being movable during the grinding operation.

4. A grinding machine having, in combination, a grinding wheel and wheel head, a table on which the work is supported with its axis substantially parallel to the axis of the wheel, means to adjust the wheel toward and from the work, automatic means to move said worksupporting table axially of thewheel over a limited range relative to the wheel, and means to limit said range of operative movement, and manual means to adjust said wheel head axially of the work over a much greater range, relative to the work, said work supporting table being movable and said wheel head being fixed durin a grinding operation.

5. In a grin ing machine, work support: ing means, a rinding wheel and wheel head, a table on WhlCh said wheel head is mounted, means togive said wheel head a rapid adjustment toward or from the work and relative to said table, and additional means to give said wheel head a fine adjustment toward or from the work.

6. In a grinding machine, work supporting means, a grinding wheel and wheel head, means to give said wheel head a rapid adjustment toward or from the work, means to retain said rapid adjustment, and additional means to give said wheel head a fine adjust ment toward or from the work.

7. In a grinding machine, work supporting means, a. grinding wheel and wheel head, a secondary slide for said wheel head, quickacting means eflfective to give said secondary slide a coarse adjustment toward and from the work, means to secure said secondary slide inadjusted position, and additional means to give said wheel head a fine adjustment on i said secondary slide toward or from the just the wheel toward and from the work, and additional means for-fine adjustment of the wheel toward or from the work.

9. In a grinding machine, a bed, a grinding wheel, means to support the grinding wheel and work to rotate on substantially parallel axes, means to move the wheel axially of the work, comprising a table for said wheel supporting means slidable on the bed, and additional means to move the work axially of the wheel comprising a table for the work supporting means paralleling the wheel table and slidable on said bed. 4 10. In a grinding machine, a bed, a grinding wheel, means to support the grinding wheel and work to rotate on substantially parallel axes, means to move the wheel axially of the work, comprising a table for said wheel supporting means slidable on the bed, and additional means to move the work axially of the wheel comprising a table for the work supporting means paralleling the wheel table and slidable on said bed, and means to move the wheel transversely on its table.

11. In a grinding machine, a bed, a grind- .ing wheel, means to support the grinding wheel and work to rotate on substantially parallel axes, means to move the wheel axially of the work, comprising a table for said wheel supporting means slidable on the bed, means to move said table over an extended range of axial adjustment, additional means to move the work axially of the wheel comprising a table for the work supporting means paralleling the wheel table and slidable on said bed, and means to move said work table over a limited range of axial travel.

12. In a grinding machine, a bed, a grinding wheel, means to support thegrinding wheel and work to rotate on substantially parallel axes, means to move the wheel axially of the work, comprising a table for said wheel supporting means slidable on the bed, means to move said table over an extended range of axial adjustment, additional means to move the work axially of the wheel comprising a table for the work supporting means paralleling the wheel table and slidable on said bed, means to move said work table over a limited range of axial travel, and means to move the wheel transversely on its table.

. 13. In a grinding machine, a bed, a grinding wheel, means to support the grinding wheel and work to rotate on substantially parallel axes, automatic means to move the "work supporting table axially of'the wheel during the grinding operation, comprising a table 'for said wheel supporting means slidable on the bed, means to move said table over an extended range of axial adjustment, additlonal means to move the work axially of the wheel. comprising a table. for the wor supporting means paralleling the wheel table and slidable on said bed, means to move said work table over a limited range of axial travel, and means to move the wheel transversely on its table.

14. In a grinding machine, a bed, a grind ing wheel, means to supporting the grinding wheel and work to rotate on substantially parallel axes, means to move the wheel axially of the work, comprising a table-for said wheel supporting means slidable on the bed, additional means to move the work axially of the wheel comprising a table for the work supporting means paralleling the wheel table and slidable on said bed, means to give said wheel a rapid adjustment toward and from the work, and additional means to give said wheel a fine adjustment toward and from the work.

15. In a grinding machine, a bed, a grinding wheel, means to support the grinding wheel and work to rotate on substantially parallel axes, means to move the wheel axially' of the work, comprising a table for said Wheel supporting means slidable on the bed, additional means to move the work axially of the wheel comprising a table for the work supporting means paralleling the wheel table and slidable on said bed, a slide on the wheel table for said wheel supporting means, quick acting means effective to give said slide a coarse adjustment toward and from the work, means to secure said slide in adjusted position, and additional means to give said wheel supporting means a fine adjustment on said slide toward or from the work.

16. In a grinding machine, work supporting means, a grinding wheel and a wheel head, a supporting for said wheel and wheel head comprising a table, a second table upon which said first table is mounted, said tables being movable toward and from the work, means to give said second table a rapid adjustment toward and from the work, and additional means to give said first mentioned table a fine adjustment toward and from the work, whereby said wheel head may be quickly moved to the work and given a fine adjustment relative thereto.

In testimony whereof I have hereunto afiixed my signature.

ERNEST A. WALKER. 

